[Doodle] Allow overriding the API URL via a fieldtrial param

components/doodle/doodle_fetcher_impl.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/doodle/doodle_fetcher_impl.h"
 
 #include <utility>
 
-#include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "components/data_use_measurement/core/data_use_user_data.h"
 #include "components/google/core/browser/google_url_tracker.h"
 #include "components/google/core/browser/google_util.h"
 #include "net/base/load_flags.h"
 #include "net/http/http_status_code.h"
 #include "net/traffic_annotation/network_traffic_annotation.h"
 #include "net/url_request/url_fetcher.h"
@@ skipping 14 matching lines @@
   const char kResponsePreamble[] = ")]}'";
 
   base::StringPiece json_sp(json);
   if (json_sp.starts_with(kResponsePreamble)) {
     json_sp.remove_prefix(strlen(kResponsePreamble));
   }
 
   return json_sp.as_string();
 }
 
-GURL BuildDoodleURL(const GURL& base_url, bool gray_background) {
-  return base_url.Resolve(
-      base::StringPrintf(kDoodleConfigPathFormat, gray_background ? 1 : 0));
+GURL BuildDoodleURL(const GURL& base_url,
+                    bool gray_background,
+                    const base::Optional<std::string>& override_url) {
+  std::string path =
+      base::StringPrintf(kDoodleConfigPathFormat, gray_background ? 1 : 0);
+  if (override_url.has_value()) {
+    // The override URL may or may not be relative to the base URL.
+    path = *override_url;
+  }
+  return base_url.Resolve(path);
 }
 
 }  // namespace
 
 DoodleFetcherImpl::DoodleFetcherImpl(
     scoped_refptr<net::URLRequestContextGetter> download_context,
     GoogleURLTracker* google_url_tracker,
     const ParseJSONCallback& json_parsing_callback,
-    bool gray_background)
+    bool gray_background,
+    const base::Optional<std::string>& override_url)
     : download_context_(download_context),
       google_url_tracker_(google_url_tracker),
       json_parsing_callback_(json_parsing_callback),
       gray_background_(gray_background),
+      override_url_(override_url),
       weak_ptr_factory_(this) {
   DCHECK(google_url_tracker_);
 }
 
 DoodleFetcherImpl::~DoodleFetcherImpl() = default;
 
 void DoodleFetcherImpl::FetchDoodle(FinishedCallback callback) {
   if (IsFetchInProgress()) {
     callbacks_.push_back(std::move(callback));
     return;  // The callback will be called for the existing request's results.
@@ skipping 14 matching lines @@
         }
         policy {
           cookies_allowed: false
           setting:
             "Choosing a non-Google search engine in Chromium settings under "
             "'Search Engine' will disable this feature."
           policy_exception_justification:
             "Not implemented, considered not useful as it does not upload any "
             "data."
         })");
-  fetcher_ =
-      URLFetcher::Create(BuildDoodleURL(GetGoogleBaseUrl(), gray_background_),
-                         URLFetcher::GET, this, traffic_annotation);
+  fetcher_ = URLFetcher::Create(
+      BuildDoodleURL(GetGoogleBaseUrl(), gray_background_, override_url_),
+      URLFetcher::GET, this, traffic_annotation);
   fetcher_->SetRequestContext(download_context_.get());
   fetcher_->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES |
                          net::LOAD_DO_NOT_SAVE_COOKIES |
                          net::LOAD_DO_NOT_SEND_AUTH_DATA);
   fetcher_->SetAutomaticallyRetryOnNetworkChanges(1);
   data_use_measurement::DataUseUserData::AttachToFetcher(
       fetcher_.get(), data_use_measurement::DataUseUserData::DOODLE);
   fetcher_->Start();
 }
 
@@ skipping 83 matching lines @@
 
 GURL DoodleFetcherImpl::GetGoogleBaseUrl() const {
   GURL cmd_line_url = google_util::CommandLineGoogleBaseURL();
   if (cmd_line_url.is_valid()) {
     return cmd_line_url;
   }
   return google_url_tracker_->google_url();
 }
 
 }  // namespace doodle